1. Field of the Invention
The present invention relates to a camera arrangement, camera system and method.
2. Description of the Prior Art
FIG. 1 shows a prior art stereoscopic image capturing camera rig 100. On such a camera rig two camera elements 105 and 110 are located on a fixing portion 115. These camera elements are separated by a fixed amount (d). The fixed amount is set so that, when displayed, the maximum positive distance between the images captured by each camera is the interpupillary distance. This is the distance between the viewer's eyes and is usually around 6.5 cm. This is to ensure that the maximum positive disparity between the two displayed images is around 6.5 cm. This allows the 3 dimensional images to be viewed on the screen.
However when capturing a scene, and in particular a landscape type scene, the fixed distance between the two camera elements 105 and 110 is not suitable for all screen sizes upon which the two images will be displayed.
This is because to achieve a displacement of 6.5 cm on a cinema screen will require a displacement between the two images of around 10 pixels for a 12.48 m screen). Therefore, if the camera rig 100 were set up to capture a stereoscopic image for display on a cinema screen, then the maximum positive displacement between the two images when displayed would be around 10 pixels. However, this displacement is not suitable for a television screen. In order to achieve a displacement of 6.5 cm on a television screen, the displacement between the two images may be 125 pixels for a 1 m screen or fewer for a larger screen. Therefore, if the images captured for display on a cinema screen were to be displayed on the television screen, the 3 dimensional effect would be negligible.
However, with advancing technology, it is possible for consumers to view 3 dimensional, stereoscopic, images in their homes. This may be on a specially configured computer display or television display (with associated viewing glasses).
This results in a problem. If a cinematic production is captured for display on a cinema screen it will not be possible to view this on a television screen whilst still maintaining the 3 dimensional effect.
It is an aim of the present invention to address this problem.